请教大家一个问题， 硬件是一样的，采样电阻接地。 负载不工作：
AD单次采样时，可以采样到0x 00;
AD+DMA连续采样，采样到 0x 0F到0x 12
抬高了采样值，
负载开起时：
AD单次采样时，可以采样到0x 67 左右波动;
AD+DMA连续采样，采样到 0x89 左右波动;
抬高了采样值，是我那里没有设置好吗，我就在例程上修改一个脚，从PC1改到PA1.
#include "adc.h"
#define ADC1_DR_Address ((u32)0x40012400+0x4c)
__IO uint16_t ADC_ConvertedValue;
//__IO u16 ADC_ConvertedValueLocal;
static void ADC1_GPIO_Config(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
/* Enable DMA clock */
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);
/* Enable ADC1 and GPIOC clock */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1 | RCC_APB2Periph_GPIOA, ENABLE);
/* Configure PC.01 as analog input */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_1;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;
GPIO_Init(GPIOA, &GPIO_InitStructure);
}
/* oˉêyÃû￡oADC1_Mode_Config
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* êäèë : ÎT
* êä3ö ￡oÎT
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*/
static void ADC1_Mode_Config(void)
{
DMA_InitTypeDef DMA_InitStructure;
ADC_InitTypeDef ADC_InitStructure;
/* DMA channel1 configuration */
DMA_DeInit(DMA1_Channel1);
DMA_InitStructure.DMA_PeripheralBaseAddr = ADC1_DR_Address;
DMA_InitStructure.DMA_MemoryBaseAddr = (u32)&ADC_ConvertedValue;
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;
DMA_InitStructure.DMA_BufferSize = 1;
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Disable;
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
DMA_InitStructure.DMA_Priority = DMA_Priority_High;
DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
DMA_Init(DMA1_Channel1, &DMA_InitStructure);
/* Enable DMA channel1 */
DMA_Cmd(DMA1_Channel1, ENABLE);
/* ADC1 configuration */
ADC_InitStructure.ADC_Mode = ADC_Mode_Independent;
ADC_InitStructure.ADC_ScanConvMode = DISABLE ;
ADC_InitStructure.ADC_ContinuousConvMode = ENABLE;
ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None;
ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
ADC_InitStructure.ADC_NbrOfChannel = 1;
ADC_Init(ADC1, &ADC_InitStructure);
ADC_RegularChannelConfig(ADC1, ADC_Channel_1, 1, ADC_SampleTime_55Cycles5);
/* Enable ADC1 DMA */
ADC_DMACmd(ADC1, ENABLE);
/* Enable ADC1 */
ADC_Cmd(ADC1, ENABLE);
ADC_ResetCalibration(ADC1);
while(ADC_GetResetCalibrationStatus(ADC1));
ADC_StartCalibration(ADC1);
while(ADC_GetCalibrationStatus(ADC1));
ADC_SoftwareStartConvCmd(ADC1, ENABLE);
}
void ADC1_Init(void)
{
ADC1_GPIO_Config();
ADC1_Mode_Config();
}
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